Compliance with impending regulations on high-frequency distortions of main ac power lines and electromagnetic emissions, is necessitating improvement in the quality of power drawn by ac-to-dc converters used in standard home and office equipment, such as personal computers, televisions, home appliances and the like. Moreover, there is an increasing demand for lightweight, very efficient, low voltage (e.g., &lt;5Vdc) power supplies for next-generation laptop/notebook personal computers. Such demanding requirements cannot all be met simultaneously by presently available power conversion methods.
Accordingly, it is desirable to provide a highly efficient ac-to-dc power converter having a high power density which provides a low voltage dc output and operates with a very high power factor.